Current control system suppressing mechanical resonance using a voltage disturbance observer

To operate two-inertia systems with high speed and precision, a control method to suppress mechanical resonance is required. A conventional current control system consists of a proportional integral controller and decoupling controller, and the conventional current control system has high motor torque control performance. However, the conventional current control system tends to excite mechanical resonance. This paper proposes a new current control system to suppress the resonance of a two-inertia system by using the cross-coupling term of a surface permanent magnet synchronous motor. The proposed control system consists of a proportional controller and voltage disturbance observer to estimate the voltage disturbance without including the cross-coupling term that is used as a damping control. The effectiveness of the proposed control system is validated by numerical simulations and experiments.